View Full Version : Help Me Read These Plugs
C5Natie
11-01-2012, 09:37 AM
The pics are Autolite 103's I had in my cam only LS3. I used them in my old high compression LS1 build but I think they're too cold for this setup (they're same as TR6's) I switched to Champion Copper 408's which are stock heat range plugs for an LS3. So do the plugs look too cold for you guys as well? The plugs were on the car about 1500 miles since I put the motor together. Ive since adjusted the timing (less of it, 28* wot) and fuel, 12.8-13.0afr wot. I don't drive long distances and I think the cooler weather as well made it worse, cold plugs couldn't burn off all the carbon.
http://i1164.photobucket.com/albums/q580/C5natie/IMAG0883-1.jpg
http://i1164.photobucket.com/albums/q580/C5natie/IMAG0884-1-1.jpg
C5Natie
11-01-2012, 09:37 AM
Some info,
LS3, stock block and heads
TSP 231/236 114lsa
LS1 coils with Taylor 8.5mm LS3 plug wires
I was seeing 28* timing at wot so I know the ecu wasnt pulling any timing and I didnt see any knock retard either. No blowby, doesnt use oil and oil looks clean. Plugs were dry also when I pulled them.
Damian
11-01-2012, 02:07 PM
http://www.angelfire.com/fl4/pontiacdude428/Readplugs.html
C5Natie
11-01-2012, 06:00 PM
Many pictures on those type of charts are either vague, low resolution so you cant see, or extreme cases. The ones in the link posted are a bit better. I just wanted to see if others agreed that they seem like plugs that were too cold for the motor. Also think the orange brownish color is from running octane booster at the track.
94cobra69ss396
11-01-2012, 06:03 PM
They look normal to me. What fuel are you running? This is one of the plugs I pulled from the Cobra with about 5,000 miles on them.
http://www.motorgen.com/pic/data/500/medium/P1030364.JPG
http://www.motorgen.com/pic/data/500/medium/P1030361.JPG
94cobra69ss396
11-01-2012, 06:05 PM
Many pictures on those type of charts are either vague, low resolution so you cant see, or extreme cases. The ones in the link posted are a bit better. I just wanted to see if others agreed that they seem like plugs that were too cold for the motor. Also think the orange brownish color is from running octane booster at the track.
It's too hard to tell the heat range with that many miles on them. Put a new set in make a quick pass and them inspect them. The red/brown color is why I asked about the fuel. The additive would be the cause.
Damian
11-01-2012, 09:23 PM
Use NGKs this time, heard too many horror stories with Autolites.
C5Natie
11-01-2012, 09:52 PM
It's too hard to tell the heat range with that many miles on them. Put a new set in make a quick pass and them inspect them. The red/brown color is why I asked about the fuel. The additive would be the cause.
I used an octane booster before i fine tuned the car. I think that caused the orange color. Car only sees 91 now, mostly chevron. Ill do a quck wot run with the new plugs and then check them out.
C5Natie
11-01-2012, 09:54 PM
Use NGKs this time, heard too many horror stories with Autolites.
Thats all ive ever used with no issues. Theyve always looked like new after months of driving. We will see with the champions now.
enkeivette
11-01-2012, 10:15 PM
I see red, what kinda fuel additives are you running?
C5Natie
11-01-2012, 10:54 PM
I ran NOS octane booster. The stuff does work a bit.
94cobra69ss396
11-01-2012, 11:19 PM
I have always run standard Autolites in everything and never had an issue.
enkeivette
11-02-2012, 12:26 AM
Hate to break your heart but it prob doesnt. The main ingredients in that pint of octane booster are Toluene or Xylene? I think it is. And you need 1 gallon straight of each, to raise ten gallons of 91 octane to 94 octane. So a pint aint gonna do shit, haha.
Go to your local paint supply store and pick up a 5 gallon drum of Toluene.
enkeivette
11-02-2012, 12:29 AM
And ya, additives prob caused the red, or I think rust might do it too... but I doubt you have that problem in a C5
Damian
11-02-2012, 02:25 AM
Mix E85 in there or run Torco if you need the extra octane. Im using E85 now to get me around 94-95 octane. Gonna go with Torco to make things easier. Torco does work, seen it with my own eyes on the dyno.
94cobra69ss396
11-02-2012, 07:37 AM
I've run a can of Torco at Adams to keep the Cobra from detonating and it works great.
C5Natie
11-02-2012, 09:23 AM
I have no need right now for the extra octane. I used to use a gallon of xylene before for my high compression motor but its $15gal now. So then I started using a mix of 30% e85 with 70% 91 for a few years and it worked great. When I used the nos it was two bottles for 1/4 tank of gas. I know its not great stuff but I have seen it work to a point. Here in CA its the only one off the shelf that might do something but you need two bottles at least. Also Im only talking about it helping for 1* or less of kr I was seeing. Not like it boost octane enough to to add timing or boost or something like that.
C5Natie
11-02-2012, 09:25 AM
Hate to break your heart but it prob doesnt. The main ingredients in that pint of octane booster are Toluene or Xylene? I think it is. And you need 1 gallon straight of each, to raise ten gallons of 91 octane to 94 octane. So a pint aint gonna do shit, haha.
Go to your local paint supply store and pick up a 5 gallon drum of Toluene.
It has a small amount of nitro methane. I think it raised 10gal up to 92 from 91 in a test. I know, not much.
C5Natie
11-02-2012, 09:28 AM
Btw this was just once, that i used octane booster, when i put the ls3 together since the old tune had too much timing in it, like 34*, but i ran cold plugs and the e85 mix. When I did try octane boosters before, they never discolored my plugs. I think the fact that the plugs werent hot enough kind of let that stuff bake on the plug this time.
C5Natie
11-02-2012, 06:24 PM
Took a short drive, gave it a quick wot here n there. Now the ground straps are all white. Wtf? Porcelain is clean, no specks.
http://i1164.photobucket.com/albums/q580/C5natie/IMAG0894-1.jpg
http://i1164.photobucket.com/albums/q580/C5natie/IMAG0895-1.jpg
The car is a bit lean while cruising but wot is still 12.8. Crappy fuel?
Vettezuki
11-02-2012, 07:07 PM
Hate to break your heart but it prob doesnt. The main ingredients in that pint of octane booster are Toluene or Xylene? I think it is. And you need 1 gallon straight of each, to raise ten gallons of 91 octane to 94 octane. So a pint aint gonna do shit, haha.
Go to your local paint supply store and pick up a 5 gallon drum of Toluene.
Torco works. It also works out to be slightly cheaper than Toluene IF you buy it in 5gal pales (for like $250 AIR). Takes maybe about a quart to do the same thing 1.5-2.0 gallons of Tolune would do in my 15gal gas tank.
Shaolin Crane
11-02-2012, 07:35 PM
My neighbor is a Torco distributor, said a case of torco costs about $100
C5Natie
11-02-2012, 07:55 PM
How bout my new plugs and how they look?....
Damian
11-02-2012, 08:58 PM
Are you using stock heat range plugs? What plug gap? I ran .044 in the GTO with TR5 plugs and it ran good.
C5Natie
11-02-2012, 09:31 PM
I believe the gap is .45, stock heat range. I wonder if i got bad gas or winter blend extra ethanol. Wierd.
Damian
11-02-2012, 10:34 PM
My neighbor is a Torco distributor, said a case of torco costs about $100
I know a guy that sells it for $120 for a case. Gonna get a case of it then get a 5 or 10 gallon drum (however big they are) and just refill the cans.
94cobra69ss396
11-02-2012, 11:19 PM
The heat range of the plug is too hot. Go one step colder and test it again.
C5Natie
11-02-2012, 11:41 PM
Then im back to what i had. Lol. Ahhhh!
94cobra69ss396
11-02-2012, 11:47 PM
See how the entire ground strap is the same color? That is a sign that it is too hot. It should change color around halfway. If it changes near the tip it is too cold.
C5Natie
11-03-2012, 11:44 AM
Ill try ngk tr6's next. Tr5 is stock, tr55 is same but with a .55 gap. Tr6 is a step colder with a .35 gap.
C5Natie
11-03-2012, 01:09 PM
Could it be that my old spark plugs were ok, heat range wise, but the octane booster that was still in the tank when I first ran the motor turned them orange? And...now the new stock heat range plugs are too hot?
C5Natie
11-03-2012, 08:02 PM
Well, I figured the car ran good all this time with the colder plugs so i put some tr6's on there. Gonna drive it a bit and see how they look. If it stil looks like theyre cold Ill put the champions back on. All I know is I shouldnt see any more rust colored deposits on it.
94cobra69ss396
11-03-2012, 09:17 PM
Could it be that my old spark plugs were ok, heat range wise, but the octane booster that was still in the tank when I first ran the motor turned them orange? And...now the new stock heat range plugs are too hot?
This is possible.
Vettezuki
11-04-2012, 11:04 PM
It has a small amount of nitro methane. I think it raised 10gal up to 92 from 91 in a test. I know, not much.
As I understand from chestry, no way. Nitro Methane does not mix with gasoline.
But Nitro propane does. It's a fantastic way to blow the holy fuck out of your engine!
Vettezuki
11-04-2012, 11:07 PM
My neighbor is a Torco distributor, said a case of torco costs about $100
How many quarts in a case? A 5 gallon pale (20 quarts) is about $250 last time I bought.
Shaolin Crane
11-04-2012, 11:46 PM
How many quarts in a case? A 5 gallon pale (20 quarts) is about $250 last time I bought.
I think 16?
Better to run AV gas mix. Its about .90 a gallon, and is something around 130 octane. A 10/90 split would be perfect to considerably bump a tank of fuel.
Vettezuki
11-05-2012, 12:38 AM
I'd have to check my garage, but I think it's 8 (if it's the same I got years ago.) The beauty of Torco is small amounts bump the octane a fair bit. Like I said, I was getting about the same results from one quart as I was getting from nearly two gallons of Toluene.
enkeivette
11-05-2012, 02:27 PM
I think white means too hot or coolant fouled??
C5Natie
11-05-2012, 05:17 PM
Well guys heres what I found....first all the whitish color is from the plating on the tip. The nickel coating gives it that color. I hadnt seen that before with my autolites because they have a black coating, not nickel. What I did go off was the color band you can see on the ground strap. With the stock heat range they were close to the base, indicating it was on the hot side. With the ngk tr6's, the mark is now closer to the middle of the strap indicating a proper heat range. I noticed the car idles very well with the ngk's and seems to rev up smoother. Also less exhaust popping on decel. Only thing now is, I did a 3rd gear wot test on the fwy today while data logging. I figured it was warm and if I would see any detonation it would be then. I got no knock and the car felt great BUT the timing at wot was 31.9* when I had tuned it at 28*. Idk why it would jump like that. Would the ecu advance the timing? Or maybe a timing table is different if im manually in 3rd? (4L65E 4spd auto). Wierd.
Vettezuki
11-05-2012, 05:45 PM
AIR, the LS ECU will "trim" timing +-. Basically, it says something like, "mmm, no knock and not too lean? well then turn it up man!"
C5Natie
11-05-2012, 09:18 PM
With the other plugs i saw 28.7-29* max. With the cold plugs, 31.9*, so you may be right. Hey as long as it aint knocking.
Damian
11-05-2012, 10:50 PM
The ECU sees things are running better and it's just running the way it's supposed to now. The NGKs really made the GTO run much smoother when I put them in.
C5Natie
12-06-2012, 04:13 PM
I took a look at the NGK's today after a few weeks of driving.
Didnt like the little black speckles on the porcelain. Im thinking I should pull another 2-3* of timing.
http://i1164.photobucket.com/albums/q580/C5natie/IMAG0992-1.jpg
Cylinder #7, the problem cyl in LS motors. Light tan color on one side of the porcelain. ?
http://i1164.photobucket.com/albums/q580/C5natie/IMAG0995-1.jpg
94cobra69ss396
12-07-2012, 07:40 AM
Those plugs look great.
C5Natie
12-07-2012, 11:24 AM
Yeah Im always paranoid but it seems the ngk tr6 were the right ones. The car runs better. Im going to Willow Springs tomorrow and I just wanted to be on the safe side. I might just bring the timing down to 26* vs 28*. Ill check the data at the track.
C5Natie
12-12-2012, 05:04 AM
Copy and pasted from my thread on CorvetteForum...
Thanks to working nights and nasty Folgers coffee, I researched and solved my spark plug dilema...I hope. Lol. For those who may find this useful....If you read this thread I changed my Autolite 103's because they looked fouled. Turned out it wasn't because they were too cold, it was because of octane booster that was in the gas tank when i installed the new motor. Anyway. I changed to NGK tr6's but started seeing slight hints of detonation, very light black specs on the porcelain, nothing crazy but they shouldnt be there and the first thread or two looked like they were getting hot, even though I always had good air fuel ratio readings (12.8-12.9 wot). So before I messed with the tune or went to a colder plug I looked into it. The tr6 plugs has an entire thread exposed into the combustion chamber, they're a thread longer then the 103's. This reduces its ability to dissipate heat into the cylinder head allowing the plug to get too hot. The Autolite 103 does not expose any threads and it is actually closer to a NGK heat range 7 (br7ef), then a tr6 in the 6 heat range, which is one lower then stock. Its design is slightly colder. In fact, the Autolite 103 appears on the cross reference for both NGK tr6 and BR7EF. Autolite usually has two plugs per other manufacturers heat range. No wonder the car ran good from the get go with them even when they looked fouled and especially since the car was tuned with them (obviously allowing for a bit more timing). So, in short, follow your gut because now I'm going back to the 103's. Posted this in case you're ever trying to decide on one of those plugs.
I should have some old Autolite 103's at home. I will try to get pictures comparing the threads to the NGK tr6.
94cobra69ss396
12-12-2012, 07:37 AM
I can't see any spots in the pictures you posted but that just may be my computer. How did yours look after running it at the track?
C5Natie
12-12-2012, 09:55 AM
I can't see any spots in the pictures you posted but that just may be my computer. How did yours look after running it at the track?
Baeically the same. Some light speckling. Its probably from some light detonation of fuel even tho I didnt read knock. I was still seeing 31* of timing on the straights wot. I would really be worried if the speckles were silver but theyre not but still it looks like theyre a bit hot. Also I need to swap over to the newer pcv system. I think my current setup is allowing too much oil vapor to get in the intake, which these cars are infamous for. Its not much but I like my intake dry. The plugs arent fouled or anything but Im not sure if any of the speckles can be attributed to a bit of oil.
C5Natie
12-12-2012, 01:19 PM
I can't see any spots in the pictures you posted but that just may be my computer. How did yours look after running it at the track?
http://i1164.photobucket.com/albums/q580/C5natie/IMAG1008-1-1.jpg
C5Natie
12-12-2012, 01:24 PM
NGK (nickel) vs Autolite 103 (dark) thread depth. NGK is half a thread longer. Tried to compare as best as possible from where the tapered seat begins, which is where it meets the head. NGK is longer. I know the Autolites sit flush in the combustion chamber, I checked it when I got the heads new. So that means the ngk must protrude which doesnt help it dissipate heat.
http://i1164.photobucket.com/albums/q580/C5natie/IMAG1012-1.jpg
http://i1164.photobucket.com/albums/q580/C5natie/IMAG1010.jpg
Camera angle might throw off the line but theyre as close as my eyes allow.
C5Natie
12-12-2012, 11:02 PM
When you use Autolite's heat range reference chart, the 103 shows up as the replacement for the TR6 and BR7EF plugs. Under Autolite the heat range is D14. It is slightly colder then the TR6.
BR7EF reference,
http://www.autolitecatalog.com/Competitor.aspx?b=A&pn=br7ef&em=True
TR6 reference,
http://www.autolitecatalog.com/Competitor.aspx?b=A&pn=tr6&em=True
As you can see, the 103 is the coldest plug in that heat range.
http://i1164.photobucket.com/albums/q580/C5natie/IMAG1005-1-1.jpg
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